1. Field of Invention
The present invention relates to the field of tools used to install, remove and maintain the magazine catches of firearms.
2. Background of the Invention
The use of tools to install, remove and maintain the magazine catches of firearms is known. Most semi-automatic and automatic firearms are provided with a means to retain a detachable box magazine in order to efficiently reload the firearm. This retention means is most commonly referred to as a magazine catch or magazine release. The structure and function of magazine catches vary, but basically they require the user to push a button or lever in order to release the magazine from the firearm.
Some designs, like magazine catches found on the H&K G3 or MP5, require the use of a punch and hammer to remove a roll pin securing the magazine catch button to the shaft of the magazine catch. The components of these releases are not designed to be easily removed for cleaning and maintenance.
Others like the transversely operable catch found on the M16A2 and M4 Carbine rely on a threaded shaft to secure the catch to a threaded button. The button and catch are elongated and fit into similar elongated slots in the receiver. The elongated design of the components keep them from unscrewing when operating within their respective slots. A magazine catch spring provides tension to the button which, in turn, pulls the catch into contact with the magazine. In order to install or remove the catch, the button must be fully depressed within its slot and held in this position. With the button fully depressed, it is possible to rotate the catch for installation or removal. When installing the catch, the user rotates the assembly a sufficient number of revolutions clockwise and aligns the catch with its elongated slot. The button is then slowly released allowing the catch to come to rest. If the user fails to rotate the catch a sufficient number of times or rotates the catch too many times, the procedure must be repeated until the end of the shaft is generally flush with the depression surface of the magazine catch button.
In order to depress the magazine catch button sufficiently, some type of tool must be used as the slot is too small for the average human finger. Several types of tools and field expedients have been used to perform this task in the past.
3. Background--Discussion of Prior Art
The use of a metal punch is recommended in technical manuals as a tool to be used to depress the button for repair or maintenance. This is due to the fact that a punch may be readily found in an armorers tool kit or mechanics tool kit. The USMC/U.S. Army field manuals call for the use of the nose of a bullet or an issue metal cleaning rod section to be used to depress the magazine catch button to adjust the magazine catch. The magazine catch button of some firearms like the M16A2 and M4 are constructed of aluminum with a hard anodizing coating and can be scratched or damaged by the nose of a bullet, a steel punch or cleaning rod section. Use of the punch is awkward and can be painful as the punch is usually held in place with the palm of the hand. The same holds true for the use of the bullet. Due to the length of the bullet, punch and the cleaning rod section, the user is unable to use the hand holding the tool to steady the firearm. Since the opposite hand is being used to install and rotate the catch, the weapon has to be held by another individual or secured in a vise before attempting the installation procedure. Starting the button into its slot against the tension of the spring can also be quite difficult when using the smooth end of the punch or conical nose of a bullet. Often times the button slips and the punch scratches or burrs the exterior finish of the aluminum receiver. Live ammunition is only issued in combat situations and therefore cannot be used during peacetime operations and training.
Other field expedients have been used to accomplish the task of depressing the magazine catch button such as an unsharpened pencil or nylon punch. These expedients do not damage the parts but they are still awkward to use and cause considerable discomfort to the hand of the user. These punch-like expedients still have many of the same limitations as the steel punch.
Damage can also be caused to the magazine catch spring when a punch or similar tool is used to fully depress the magazine catch spring. When a coil spring is allowed to be compressed to a "solid" state (all coils touching) the spring takes a "set" weakening the spring and possibly causing magazine retention failure. Care must be taken to depress the spring only enough to install the catch and not to allow the spring to "go solid". It is virtually impossible to accomplish this metered depression of the magazine catch button without some limiting means that is incorporated into the tool.
Inventors have created several types of tools to maintain firearms like the M16A2 and M4 Carbine.
One invention, U.S. Pat. No. 4,819,289 to Gibbs, Apr. 11, 1989, is basically a combination tool designed to perform multiple adjustments and mechanical operations to a firearm and its accessories. While this tool could be used to perform the task of depressing the magazine catch button, it still has many of the disadvantages that are associated with the other prior art references previously discussed. The blade most suited to the task is of a narrow screwdriver configuration and is constructed of steel. The user would have difficulty starting the magazine catch button into the slot with this tool and its length would also call for the use of a vise or another individual to steady the weapon. This blade is also pivotally attached to its handle and lacking a locking feature. It is likely that the user would experience difficulty in keeping the blade extended to accomplish the task of depressing the magazine catch button. If the blade folded during the operation, damage to the firearm and components or loss of components would result. The blade also lacks a limiting means to protect the magazine catch spring from the damage caused by over insertion of the magazine catch button.
Another invention, U.S. Pat. No. 3,564,950 to Jorczak, Feb. 23, 1971, although specifically designed as a cartridge extraction device, could also be used to depress the magazine catch button. In this capacity the opposite end of the extractor claw would serve as a punch. All of the disadvantages discussed previously also apply to this expedient. Those being, damage to the firearm or parts due to steel construction, awkward use due to the tools length, a lack of a depression limiting means and discomfort or injury to the hand of the user from the extractor claw of the tool.
It should be clear to the reader that a tool that allows an individual to simultaneously hold a magazine catch button in a depressed state and steady the firearm with the same hand is of great necessity. It should also be clear that the tool should be made of a non-marring material, should not cause discomfort to the user and should be designed to aid in the alignment and insertion of the magazine catch button into the receiver. Lastly, it should be clear that the tool should be designed to limit the amount of insertion of the magazine catch button to protect against weakening of the magazine catch spring.
All of the other prior art references cited have one or more of the disadvantages previously discussed associated with their use -to accomplish the task of depressing the magazine catch button.